1. Field of the Invention
The present invention is in the field of cleaning and decontaminating surgical instruments and other medical paraphernalia used in healthcare facilities. This cleaning and decontamination takes place as a preliminary step subsequent to use and soiling of the surgical instruments, and prior to their sterilization by autoclave.
Heretofore, it has been a common practice to merely place used surgical instruments and paraphernalia on towels or in a covered pan prior to their being sent to a central service facility for sterilization by autoclave, an apparatus which uses superheated steam under pressure to achieve total microbiological decontamination. Thus, no precautions have usually been taken to prevent the transmission of tissue and blood-borne diseases which may take place when personnel working with the soiled surgical instruments accidentally suffer cuts or punctures from these sharp instruments and thereby come in direct contact with blood and tissue on the soiled instruments. Because sterilization was being achieved in the autoclaving process, prior cleaning may have been carried out, but a disinfecting step was either carried out by a separate step or considered redundant, and therefore not used.
More recently, however, there has been widespread concern about the transmission of very serious and often fatal diseases, such as nosocomial infections from resistant strains of bacteria which commonly arise in healthcare facilities, and by viruses carried in tissues and blood, such as hepatitis B and HIV, which may be transmitted to personnel dealing with soiled surgical instruments, as described above.
But, it has been difficult to achieve microbiological decontamination by a method that is vigorous enough to kill resistant strains of Staphylococus aureus and Pseudomonas aeruginosa, and viruses such as hepatitis B and HIV, while at the same time being simple and straightforward enough to be accomplished with a minimum expenditure of time after the surgical instruments have been used, by personnel requiring a minimum amount of training, and using apparatus and materials which are both inexpensive and reliable. Moreover, it has typically been a problem that the surgical instruments and other paraphernalia may be grossly soiled, and therefore require vigorous cleaning in addition to initial decontamination. Unfortunately, compositions are not available which will accomplish both the vigorous cleaning of grossly soiled surgical instruments and their microbiological decontamination. This problem has been further augmented by the fact that cleaning and decontaminating compositions are usually incompatible for a variety of reasons. Thus, heretofore, it has not been possible to readily combine both the cleaning and decontaminating of surgical instruments into an efficient method.
2. Brief Description of the Prior Art
A number of different methods are known in the art for disinfecting or decontaminating surgical instruments and other medical paraphernalia. See, e.g., Bertil Nystrom, 1981 Journal of Hospital Infection, 2, 363-368.
Mild cleaning and disinfecting products are known in the art, e.g., germicidal detergents such as a phenolic-based disinfectant. However, it has not been known or suggested that such germicidal detergents be combined with more vigorous cleaning agents such as enzyme-based presoaks for medical apparatuses and instruments. In the literature for such an enzyme-based presoak, it is usually recommended that any items requiring sterilization or disinfection should be treated in a separate subsequent step. Compatibility of such enzyme-based presoaks with strong disinfectants is also a recognized problem. For example, it is well known that anionic detergents deactivate protease enzymes.
For example, Thomasen U.S. Pat. No. 4,867,797 discloses a method for cleaning instruments used for analyzing protein-containing biological liquids which utilizes an enzyme rinse solution, but uses germicides therewith only in low concentrations and only to increase the stability of the enzyme composition by protecting it against microbial deterioration.